On Mon, 2019-06-17 at 11:35 -0700, Prakhar Srivastava wrote: > Currently during soft reboot(kexec_file_load) boot command line > arguments are not measured. Define hooks needed to measure kexec > command line arguments during soft reboot(kexec_file_load). > > - A new ima hook ima_kexec_cmdline is defined to be called by the > kexec code. > - A new function process_buffer_measurement is defined to measure > the buffer hash into the IMA measurement list. > - A new func policy KEXEC_CMDLINE is defined to control the > measurement.[Suggested by Mimi] > > Signed-off-by: Prakhar Srivastava <[email protected]>
With minor changes below, Reviewed-by: Mimi Zohar <[email protected]> > --- > diff --git a/security/integrity/ima/ima_main.c > b/security/integrity/ima/ima_main.c > index af341a80118f..1e233417a7af 100644 > --- a/security/integrity/ima/ima_main.c > +++ b/security/integrity/ima/ima_main.c > @@ -605,6 +605,80 @@ int ima_load_data(enum kernel_load_data_id id) > return 0; > } > > +/* > + * process_buffer_measurement - Measure the buffer to ima log. > + * @buf: pointer to the buffer that needs to be added to the log. > + * @size: size of buffer(in bytes). > + * @eventname: event name to be used for the buffer entry. > + * @cred: a pointer to a credentials structure for user validation. > + * @secid: the secid of the task to be validated. > + * > + * Based on policy, the buffer is measured into the ima log. > + */ > +static void process_buffer_measurement(const void *buf, int size, > + const char *eventname, > + const struct cred *cred, u32 secid) > +{ > + int ret = 0; > + struct ima_template_entry *entry = NULL; > + struct integrity_iint_cache iint = {}; > + struct ima_event_data event_data = {.iint = &iint }; > + struct ima_template_desc *template_desc = NULL; > + struct { > + struct ima_digest_data hdr; > + char digest[IMA_MAX_DIGEST_SIZE]; > + } hash = {}; > + int violation = 0; > + int pcr = CONFIG_IMA_MEASURE_PCR_IDX; > + int action = 0; > + > + action = ima_get_action(NULL, cred, secid, 0, KEXEC_CMDLINE, &pcr, > + &template_desc); > + if (!(action & IMA_MEASURE)) > + goto out; "out:" is a simple return, no freeing memory. Just return here. > + > + event_data.filename = eventname; No need to initialize even_data.filename, here initialize it when it is defined. > + > + iint.ima_hash = &hash.hdr; > + iint.ima_hash->algo = ima_hash_algo; > + iint.ima_hash->length = hash_digest_size[ima_hash_algo]; > + > + ret = ima_calc_buffer_hash(buf, size, iint.ima_hash); > + if (ret < 0) > + goto out; > + > + ret = ima_alloc_init_template(&event_data, &entry, template_desc); > + if (ret < 0) > + goto out; > + > + if (action & IMA_MEASURE) Why is this test needed again? Mimi > + ret = ima_store_template(entry, violation, NULL, buf, pcr); > + > + if (ret < 0) > + ima_free_template_entry(entry); > + > +out: > + return; > +} > + > +/** > + * ima_kexec_cmdline - measure kexec cmdline boot args > + * @buf: pointer to buffer > + * @size: size of buffer > + * > + * Buffers can only be measured, not appraised. > + */ > +void ima_kexec_cmdline(const void *buf, int size) > +{ > + u32 secid; > + > + if (buf && size != 0) { > + security_task_getsecid(current, &secid); > + process_buffer_measurement(buf, size, "kexec-cmdline", > + current_cred(), secid); > + } > +} > + > static int __init init_ima(void) > { > int error; >
